Hydraulic road grader



ot.13,1936; 4.-. o. 'D WLLAR 2,057,089

` HYDRAULIC ROAD GRADER Filed Feb. 2b, 1953 4 sheets-sheet 4 /N vll-:NTo R Hoya 0 DeMi//alr' Patented Oct.l 13, 1936- UNITEDI STATES PATENTOFFICE HYDRAULIC ROAD HEADER.

Application February 20, 1933. Serial No. 651,666

34Claim8.

My invention relates to the adaptation of uidpressure motor-operatedadjusting mechanism, particularly of the hydraulic type, to road workingand road building machinery, and one of the objects of my invention isthe provision oi' improved and eilicient fluid-pressure controllingapparatus for adjusting various parts of such machinery by means ofduid-pressure motors and enabling a rotary duid-pressure pump to operatecontinuously at substantially no volume and substantially no load whenthe motors are inactive.

Another object of the invention is the provision in road-workingapparatus of means for controlling from a single operators station aplurality of hydraulic motors distributed about the machine andautomatically limiting the hydraulic pressure which may be exerted inany of the hydraulic motors.

Another object of the invention is the provision in a road grader ofcontrolling apparatus for double acting hydraulic motors distributedabout the machine, which controlling apparatus shall includeA aplurality of valves banked at the operators station to enable theoperator to actuate such valves at such station to effect desiredadjustments of various parts of the machine.

Another object of the invention is the provision of hydraulic steeringmechanism for a vehicle combined with valve mechanism located at theoperators station at the rear end of the machine for enabling acontinuously operated rotary pump to supply pressure whenever desired toeffect the steering operation.

A lurther'object ofl the, invention is the provision in a road grader ofa plurality of hydraulic motors for adjusting the height and lateralpositions of a mold board combined with a plurality of valves at theoperators station at the rear lend of the machine to accurately controlsaid hydraulic motors and effect locking thereof in adjusted positions.

Other objects of the invention will appear hereinafter, the novelfeatures and combinations being set forth in the appended claims.

In the accompanying drawings Fig. 1 is an elevation of a. road gradingmachine illustrating one of the adaptations of my improvements;

Fig. 2 is a plan view of the structure shown v' in Fig. 1;

Fig. 3 is a rear elevation of the machine shown in Fig. l;

Fig. 4 is an elevational View partly in section taken on the line 4-4 ofFig. 1 looking in the 55 direction of the arrows;

(Cl. .3T-156) Fig. 5 is a sectional elevation of my improved rotary pumpin zero position? Fig. 6 is a view similar to Fig. 5 but with the partsin operating position;

Fig. 7 is a sectional elevation on the line 1-1 of 5 Fig. 5 looking inthe direction of the arrows, the pipes being shown in elevation;

Fig. 8 is a sectional elevation of a manual controlling valve; and

`Fig. 9 is a diagrammatic piping diagram for l0 the rotary pump andhydraulic motors mounted on the road grader shown in Figs. 1 and 2.

The machine shown in Figs. 1 and 2 comprises a vehicle frame mounted onthe iront wheels I2, I2 and rear wheels |3, I3. The frame l5 compriseslongitudinal spaced-apart beams I4, i4 which are rigidly connected bythe tubular cross-pieces i5, I6 and |1.

As shown in Fig. 4 the forward ends oi the beams I4, I4 are connected bya U-shaped yoke' 20 I9 which rests upon a supporting frame 20 havingdepending channel irons 2|, 2| secured at their lower ends to theaxle-tree 22 on the ends of which are pivoted at 23, 23 the axles forthe iront wheels I2, I2. These axles are provided 25 with vertical arms24, 24 to the upper ends oi which is pivoted the cross-piece 25.

Between one of the channel irons 2| and one o! the arms 24 is pivotallyconnected a hydraulic motor comprising a cylinder 26 and a piston rod 3021. The cylinder 26 is pivoted at 26' to one of the channel irons 2| andthe piston rod 21 is pivoted at 28 to the right-hand vertical arm 24 asviewed in Fig. 4. As hereinafter explained, the hydraulic motorcomprising the cylinder 26 is 35 double actingl in that the liquid flowsinto and out of the cylinder on both sides of the piston therein andtherefore when the leaning of the wheels l2 is adjusted they may belocked in adjusted positions by closing the valve controlling the ow 4,0oi' the liquid in the cylinder 26.

Figs. 1 and 2 illustrate a pull type grader having a vehicle tongue 29secured at 30 to a vertical post 3|, the upper end of which is pivotedat 32 to the frame 20 andthe lower end of which is 45 pivoted at 33 tothe front angle 22 of the axletree 22.

A cross-piece 34 secured to the tongue 29, as shown in Fig. 2, providesat its ends pivotal supports at 35, 36 for the cylinders 31. 38 of hy-50 draulic motors comprising piston rods 31', 38', the outer ends ofwhich are pivoted at 40, 4I to clips 40' and 4| secured to the frontaxle-tree 22 and to the channels 2|. While in some instances one doubleacting hydraulic motor comportion of the frame are two metal pi beemployed. I prefer to use two hydraulic motors symmetrically arranged asshown in Pig. 2.

AsshowninFlgs. 1and2,acrossp1ate42is secured to the upper sides of theforward ends of the sidebeams |4, |4 and secured to this plate 42 anddepending therefrom is a vertical fixed bearing rod-40, the lower end ofwhich is provided with a retaining cap 44 as shown in Fig. 4. When thehydraulic steering mechanism is operated the frame 20 turns on avertical axis at the center of the bearing 40.

Secured to the bottom of the plate 42 concentricwith the bearing rod 40yis a gear housing 40. When the crank 45' is operated, wormfgearing inthe housing 40 turns a screw 40 in the nut 41 to which is pivoted at 40,40 the yoke 40v which in turn is pivoted at 00 to the front end of thedrawbar 0|. It will thus be seen thatby t ning the crank 40' the frontend of the draw may be elevated or lowered relative to the mainframeSecured to the top of the plate 42 is a socket 52 in which is mounted avertical post 00 which may be held rigidly in vertical position by meansof any desired construction. To the top o f the post 50 is pivotallyconnected at Il the inclined plate 08, the forward end of which issecured to the loop 00 and the latter connected to a spring 00 which isconnected at its front end to the Clips 0|, 0|. are relied on to securefour flexible lconduits 82, 00 and -04, 00 to the plate l0. The

conduits 62, 00 are connected to the steering motors 01 and 00 and theconduits 04, 05 are connected to the motor 20 for adjusting the leaningof the front wheels I2.

'Mounted on a cross-piece 00 on the fo ard 01 and 00 which arerespectively connected to the ilexible conduits 02 and 00. The metalpipes 01 and 00 extend to the rear portion of the frame I where they areconnected directly to the valve manifold as hereinafter more fullyexplained Secured rigidly to the 'rear ends of the longitudinal beams |4is a guide frame 02 comprising angle irons 00, 00 as shown in Fig. 3.Guides are provided at 00, 00 for the transverse members 01, 01 of therear wheel supporting frame. 'I'he axles 00, 00 for the rear wheels |0,|0 are pivoted at 00, 00 at the ends oi' the frame 01. Secured to therear wheel axles are vertical crank arms 00, 00I the upper ends of whichare pivoted at 0|,0|tothecrossp iece 02.

A vertical bracket plate 00 is secured to the frame 01 and to its upperend at 04 is pivoted a cylinder ,05 of a hydraulic moton comprising apiston rod 00, the outer end of which is pivoted at 0| to the upper endof the crank arm 00 as shown in Fig. 3. The. hydraulic motor comprisingthe cylinder 0l is double acting in that the liquid flows to and fromthe cylinder 00 on both sides of the piston therein and the controllingvalve is such that when it is closed the crank arms 00, 00

vwould be locked in adjusted positions. The leannf the beams I4, |4.

Referring now to the road-working implement comprising a mold board orscraper |00 and the structure for supporting the same, it will be seenthat the. drawbar 0| comprises spaced-apart members |00. |01 whichdiverge rearwardly and have secured to the rear portions thereof asupporting circular guide |00 for supportingy and guiding thecircleframe |00 yon which the mold board |05 is mounted. By means of gearingH0 connected by links I and universal joints ||2 to| the wheel ||0 atthe operators station, the

circle |00 and themold board'l0l may be-adjusted angularly relative tothe path of travel of the road grading machine. By means of the Itshould be understood that the circular guide with the drawbar, and themold board |00 moves f bodily with the guide frame |00 and the drawbarIl.

To diametrically opposite sides of the circular guide frame |00 areconnected by means of universal joints ||1 and |I0-the lowerends ofextensible hanger rods ||0 and I 20. Each' hanger rod comprises a lowerrod |2| telescoping into a pipe rod |22. Holes |20,|20 in the pipe |22are adapted to register with a transverse hole in the rod |2| and a pinrelied on to connectthe rod-ill to the pipe |22 after the length of thehanger has been adjusted. Whileln Fig. 1 provision is made for twodifferent length of the hanger ||0 there may be more than two holes |20if desired.

The upper ends of the hangers ||0 and |20 are connected by the universaljoints |24 and |20 to the crank arms |20 and |21 which extend laterallyfrom the longitudinal rockshafts |20 and |20.

. The rockshai'ts are mounted in suitable bearings |00. |0| and |02, |00on the'tops of beams I4. I4 and spaced above the samel a suiiicientdistance to aii'ord ample clearance between the the piston rods |00,|00' which extend downwardly into the cylinders |00 and |40'of hydraulicmotors mounted on opposite sides of the rear portion of the frame Ii asshown in Fig. 2. The lower ends of the cylinders |00 and |40 are pivotedat |4|, |42 to brackets depending from the beams I4.

The hydraulic motors comprising the cylinders |00 and |40 are preferablydouble acting under control of valves locatedat the operators station.Consequently, when the mold board has been adiusted it may be locked inadjusted position against both up and down movements.

The mold board may be shifted laterally relatively to the frame by meansof the hydraulic motor comprising the cylinder |44 and connectionsbetween the same and the rear end of the drawbar 0|. The upper end oi'the cylinder- |44 is pivoted at |40 to a bracket |40 mounted on thecross-tube |1 as shown inll'igs. l and 2.

'Ihepistonrod |41isconnectedto arackbar sts cranks |20 and |21 andthemain frame Il when 41 which is guided by a roller |48 and which mesheswith the pinion |49 secured to a shaft to the lower end of which issecured a gear meshing with the transverse rack bar |52. bar |52 issupported by and guided along a transverse rail |50 secured to the lowersides of the beams |4 as shown in Fig. 1.

Between a pair of lugs |53'is pivoted at |54 a clevis |55 and the latteris pivoted on an upright 1" axis to a rod |56 which is adapted to slidein the longitudinal guide |51 on the bottom of the plate |58. The plate|58 is pivoted at |59 to the crosspiece |60 of a semi-circular frame. atthe center of the arcuate member |6| thereof. This arcuate member isprovided with a pluralityof notches |62 for receiving the latchmechanism |63.

A semi-circular frame comprising the crosspiece |60 and the arcuatemember |8| is pivoted at |64 to the rear end of the drawbar .5|. Thelatch mechanism may be released manually and the motor I operated tomove the rack |52 along the guide |50 and thus snap the latch mechanisminto another notch |62. Then upon reversing the motor l". power may beapplied to shift the mold board laterally relative to the machine frameIt should be understood that the shifting of the mold board laterallyand the adjustment thereof vertically may be effected by hydraulic motormechanism entirely. The construction is such that the mold board may bemoved by means of the hydraulic motor mechanism to high-lift orbank-sloping position on either side of the machine. Since the hydraulicmotors are double acting4 they may be-relied upon to lock the mold boardat adjusted elevation whether occupying a horizontal position oroccupying a high-lift or bank-sloping position.

The above described apparatus for adjusting the mold-board to variouspositions relative to the main frame, including the extensible hangersand the laterally shifting mechanism, is described and claimed in theapplication of Franklin E. Arndt, Serial No. 646,997, nled December 13,1932, for an improvement in Road graders. lIn the application ofFranklin E. Arndt. Serial No. 18.409, filed April 26, 1935 for animprovement in Road graders and as a division of Serial No. 654,901, ledFebruary 2, 1933 for an improvement in Road graders, the hydraulicsteering mechanism shown at the left hand ends of Figs. 1 and 2 of theaccompanying drawings, is disclosed and claimed,

but the claims hereto appended are directed to improvements notdisclosed in any of said Arndt applications.

I'he internal combustion engine |16 and the pump |11 to which it isconnected, are mounted on suitable supporting framework at the rear endof the machine frame as shown in Fig. 3. The fluid-pressure medium, suchas oil, is drawn from the supply tank |18 by the pump |11 and forcedthrough the various pipes or conduits shown in Fig. 9.

The valves for the respective hydraulic motors are banked in asingleposition adjacent to the operator-s station at the platform which islocated at the rear end of the machine. Inasmuch as the machine shown inFig. 1 includes six adjusting hydraulic motors and one double steeringhydraulic motor mechanism, I have shown seven controlling valves eachhaving the construction shown in Fig. 8 and each comprising a valvehousing |19 mounted on a manifoldrl19. Each valve may be manuallyoperated by means of a lever |30. By referring to Figs. 2 and 9 it willbe seen that the end knobs I 8| and |82 may be con.-

The rack .ders 206 in the rotary cylinder block |92.

nected to levers |80 for operating valves to control the motors |39 and|40. The knob |83 may be connected tothe front leaning wheel motor 28.The knob |84 may be connected to the valve for controlling the motors 31and 38 to operate them in opposite directions so that whenever thepiston rod 31' is moved in one direction, the other piston rod 38 may bemoved in the opposite direction.

The knob |85 may be connected to the valve for controlling the motor|44. The knob |88 may be connected to the valve for controlling the rearshifting motor 81. The knob |81 may be conl nected to the valve forcontrolling the rear leanthe suction pipe |88 to the supply tank |18.

Since the pump |11 is operated continuously by the internal combustionengine the liquid is under pressure in the pipe |89. Inasmuch as it isdesirable to operate the pump at substantially no volume and load whenall oi the motor controlling valves are closed, a branch pipe 239 isconnected to the supply pipe |89 as shown in Fig. 5 for enabling thefluid-pressure in the pipe |89 to operate mechanism to hold the pump inzero position.

Assuming that the manually 'operated controlling valves on the manifold|19 at the operators station are all closed, the rotary pump |11 willhave all its moving parts concentrically arranged as shown in Fig. 5 andtherefore the engine may continue to operate at very little or no loadsince the pump is in zero position. Consequently, the pump may be drivencontinuously with the consumption of a minimum amount of fuel duringoperation of the road grader with the various devices thereon locked andheldin adjusted positions. y A

'I'he pump |11 shown in Fig. 5 comprises a housing |90 mounted on thetank |18 which may be secured to the beams I4, I4 of the road grader.Within the chamber |9| in the housing |90 are mounted the rotating partsof the pump conrprising a multiple cylinder block |92 journaled on thebearing |93. The pump housing |90 preferably consists of two sections|90' and |90" secured together by means of the cap screws 294 as shownin Fig. 7.

The bearing |93 intermediate its ends is provided with a collar |94adapted to flt into an annular seat at the inner center of the face ofthe section |90'. The right-hand end of the bearing |93 is provided witha screw-threaded rod |95 adapted to receive a nut |96. A circularclamping plate |91 engages at its peripheral edge the outer face of thecircular support |98 and a washer |99 intervenes between the clamp plate|91 and the right-hand end of the bearing |93. .By tightening the nut|96 the collar |94 is clamped to its seat and in order to preventturning ofthe bearing |93 from its desired location a key 200 ts in waysin the upper central portion of the opening in the support |98 and inthe upper side of the bearing |93 as shown in Fig. 7.

The bearing member |93 is provided with two longitudinal chambers and202 separated from' each other by the horizontal partition 283. Thelower chamber 20| is provided with an intake port'204 in communicationwith the suction pipe i88 and with a discharge port 205 adapted tocommunicate successively with the radial cylin- 'I'he upper chamber 202is provided with an intake port 201'.which is adapted to communicatesucccssively with cylinders 206 and with a discharge port2|l8 whichcommunicates with the discharge 'pipe las. 'rnc ewcys or zal ma .f 292may be formed bygboring the bearing |99 and closing theleft-.hand endsofthe cylindrical recesses by means of the screwplugs 299. 2|9. The

'perte zu, zu and n1,-.z`n.may be formed by tangential milling. ,l l l Y'I'he driving shaft 2|| which is adapted to be connected to thecontinuislyoperating internal combustion engine' |19 is journaledin abearing v m secured to the left-hand vend ci' the, cylindrical support2|9 at the central portion of the pump housing sectionvl9l". Secured ltothe inner end rotated on the bearing |99 to move the lower cylindersinto communication with the port 299 and the upper cylinders intocommunication with the port 291 as shown in Fig. 5. Accuracy of suchcommunication is assured by the end peripheral edges of the cylinderblock fitting annular bearing seats at 2|9 and 229 on the inner faces ofthepump housing sections |99' and |99".

Flttin`g in the cylinders 299 for reciprocation thereinits a'pluralityof pistons 22| the outer ends vof which bear against an abutment ring222.

Spaced from the ring 222 and concentric therewith is another ring 229 oflarger diameter which is mounted between the top abutment 229 and thebottom abutment 229. As shown in Fig. 'l the` outer. ring 229 at itsupper side is also confinedagainst movement axially of the cylinderblock l|92 by the slide seats 229 and 221 at the upper inner sides ofthe pump housing sections |99" and |99'. The lower side of the'outerring 229 is also confined against axial movement relatively to thecylinder block I|92 bythe slide seats 229 and 229 at the lower innersides ot the pump 'housing sections |99" and |99.

. A ball bearing between the rings 222 and 229 is formed bytheraces 299,29| in which travel the plurality of balls 292. This ball bearing servesto hold'the inner ring 222 in adjusted'position relative to thecylinders 22| and against axial movement relatively to the cylinderblock |92. Such ball bearing also permits the outer ring to be heldstationary while the innerV ring rotates with the pistons 22|. 1fdesired. only one ringmaybe usedinwhich eventthe outerends of thepistons will slide along the inner surface of the ring but I prefer toemploy the construction as shown togreatly minimize the wear between theouter ends of the pistons and the ring engaged thereby.

The Youter ring 229 at its diametrically horizontal opposite sides ntsbetween slide bearings 299 and 299 at the corresponding inner sides ofthe pump housing |99. While the ball bearing unit comprising theconcentric rings 222 and 229 cannot move up or down relatively to thepump housing |99 it may move to a limited extent glmetrlcally alongtheslide bearings 299 and Bearing against'the left-hand side of the ballbearing unit as viewed in Figs. 5 and 6 is a plunger 299 slidable in anopening in the' housing |99. A casing 299 secured at 291 to the housing|99 houses a spring 299 which acts o'n the plunger' 299 to press itconstantly against the outer ring m. p

Bearing against the right-hand side of the ball bearing unit as viewedin Figs. 5 and 6 is'a plunger 299 slidable horizontally in the bearing2l I. Hydraulic pressure in the branch pipe 239 is adapted to act on theright-hand end of the plunger 299 to force it to the left against theaction of the spring-pressed plunger 299. Fig. 5' shows the position ofthe parts for zero operar tion of the pump since in this position theball bearing unit is concentric with the axis of rotation` of thecylinder block |92. Fig. 6 shows the position of the parts when thepressure in the pipe 299 has been sumciently reduced to permit thespring 299 to act to move the ball bearing unit to its eccentricposition where the inner ring 222 will act as an abutment to effectreciprocation of the pistons upon rotation of the cylinder block |92.

Assuming the beu bearing unit is in its eccentric v position and thecylinder block |92 rotating anticlockwise as indicated by the arrow 292centrifugal force tends to throw the pistons outwardly against the innerring 222. The vlower cylinders being in communication through the port205, passageway 29| and port 299 with the suction pipe |99 liquid willbe drawn into the lower cylinders as the pistons move outwardly. As eachcylinder is cut on.' from communication with the port 299 it ceases tomove outwardly and as soon as each cylinder communicates with the upperport 291 the corresponding piston is forced inwardly by the innereccentric ring 222., When such inward movement occurs the liquid isforced into the port 291 along the passageway 292 and gut through theport 299 into the supply pipe |99. `It should be noted that when eachpiston is moving in or out while horizontal, the piston is in a neutralposition, the inner end of the cylinder being closed.

When the pistons are moving upwardly the arc between their endslengthens and therefore there ring bothwhen the arc lengthens and whenit. shortens thereby causing the ring 222 to lag.

slightly behindl the cylinderl block and pistons. The sliding of the`outer ends of the pistons is very much smaller than when a stationaryabutment ring is used.

Fig. 9 is a piping diagram showing a. series of hand-operated valvedevices mounted on the manifold |19 and each having the constructionshown in Fig. 8. 'I'he valve housing |19 is provided with a port 299which communicates with the supply passageway 299 which is common tolall of the manual valve devices shown in Fig. 9. In this view I haveshown the supply pipe |99 connected by the branch pipes 229' to thesupply passages 299. Under each valve housing |19' is a pair ofpasageways 299, 299 which are adapted to be connected to a pair of pipesleading to a hydraulic motor. For instance, in Fig. 9 'the pipes 92, 99are connected to the motors 91, 99 :aid the pipes 99, 99 are connectedto the motor 'Ihe valve shown in Fig. 8 comprises connected pistons 241,299 slidable in bearings 299, 259 and provided with an actuating rod25|., The outer end of this rod is connected by means of the link 252 toa vertical lever |80, the lower end of which is pivoted at 254 to thebracket 255 secured to the housing |19'.

When the lever is pushed to the right as viewed in Fig. 8 the supplypassageway 244 isconnected through the port 251 to the passageway 245and thence to a hydraulic motor at one side of the piston therein. Atthe same timethe other side of the piston is connected through thepassageway 246 and the port 25,9 to the discharge passageway 260 whichis connected to the pipe 26| leading back to the tank |18 as shown inFig. 9.

The system illustrated in Fig. 9 shows a branch pipe 239' connected bythe pipes 239" to the valve housing |19 through a port 244 extendingthrough the manifold |19. The manifold |19 is connected by a pipe 244'to the supply pipe |89, which leads to the pump |11. Fluid pressure frompipe |89 acts' on the plunger 240 to move the rings 222 and 223 intoneutral position, as previously described, when the valves are closed.Therefore when all of the levers |80 are released and the springs 262hold the valves in closed position the plunger 240 is pushed to the leftas shown in Fig. 5 and the rotary pump although continuing to rotatedoes not cause any flow of liquid.

With the system as illustrated in Fig. 9, the connection from supplypipe |89 to the plunger 240 will be through one of the non-operated handvalves, and the branch pipe 239 may be omitted. However, if said branchpipe 23S is employed, then branch pipes 239" may be omitted.

When any hand valve shown in Fig. 9 is'opened the relief of hydraulicpressure on the plunger 240 is suilicient to permit the spring 238Vtomove the ball bearing unit to the right as viewed in Fig. 6 and hold itthere.- The pump then operates to produce sufcient hydraulic pressure tooperate the hydraulic motor to which the manual valve is connected. Whenthe piston in the operating motor reaches the end of its stroke and itscontrolling valve is still open, assuming all of the other motors lockedby closure of their valves, the hydraulic pressure in the branch pipes239', 239" will be suillcient to set the rotary pump automatically atzero. When this occurs the pressure in the branch pipes 239', 239" willbe confined so as to lock the pump in such zero position.

It will thus be seen that in providing the automatic mechanism forshifting the ball bearing unit'to its concentric position the engine maycontinue to rotate the pump with very little power and this automaticmechanism protects the motors as well as the pump without the use of anycheck valves or pressure regulators.

Obviously those skilled in the art may make various changes in thedetails and arrangement of parts without departing from the spirit andscope of the invention as defined by the claims hereto appended, and Iwish therefore not to be restricted to the precise construction hereindisclosed.

Having thus described and shown an embodiment of my invention, what Idesire to secure by vLetters Patent of the United States is:

1. In road working apparatus, the combination with a portable frame, ofa plurality of adjustable devices carried thereby, a plurality ofhydraulic motors respectively connected to said adjustable devices, aplurality of valves one for each ot said hydraulic motors, a rotarypump,

means for continuously operating said pump, and means adapted always toact directly on the pump to set it to rotate at substantially no loadwhen said motors are not operating.

2. In a road grader, the combination with portable frame, of a roadworking implement carried thereby, means comprising two hydraulic motorsfor adjusting said road working implement and locking the same inadjusted position, valves for controlling said motors, mechanism forsupporting said valves at a single operators sta- Lion, a rotary pump,an internal combustion engine connected to said pump to continuouslyoperate the same, and mechanism acting on the pump to set the same tooperate at substantially no load when both of said valves are closed andthe road working implement is locked in adjusted position and to set thesame to operate to produce sufficient hydraulic pressure to cause eithermotor to respond to its valve when the latter is actuated.

3. In a road grader, the combination with a vehicle, of a plurality ofadjustable devices mounted thereon including an adjustable road Workingimplement, a plurality of double ,acting .hydraulic motors connected tosaid devices to adjust the same, a plurality of valves one for each ofsaid motors, means comprising a manifold to bank said valves in oneposition adjacent to the operators station, a rotary pump connectedthrough said valves to said motors, and means acting on said pump to setthe se me at zero when said valves are closed and to automatically pro-`cluce suicient fluid-pressure to operate any motor when its valve isopened.

4. In a road working machine, the combination with a vehicle, ofadjustable mechanism carried thereby, av fluid-pressure motor connectedto said mechanism to adjust the same, a valve for controlling saidfluid-pressure motor, a fluidpressure pump, means for continuouslydriving said pump, and means adapted to move an element of said pumpalways to enable said pump to be driven with substantially no loadthereon whenever said valve is closed.

5. In a road working machine, thecombination with a vehicle, ofadjustable mechanism carried thereby, a hydraulic motor connectedto-said mechanism to adjust the same, a valve for con trolling saidmotor, a rotary pump, a continuous pressure conduit completely iilledwith liquid connecting said valve and pump, an engine for con tinuouslydriving said pump, and means responsive to hydraulic pressure forcontrolling said pump always to operate with substantially no loadthereon whenever said motor is inactive.

6. In a road machine, the combination with a vehicle, of meanscomprising a hydraulic motor to steer the same, a valve for controllingsaid motor, a pump, an engine connected to said pump to continuallydrive the same, and means responsive to hydraulic pressure to enablesaid pump to operate at substantially no load when said motor isinactive.

'1. In a road machine, the combination with a vehicle, of meanscomprising a double acting hydraulic motor to steer the same, a valve tocontrol said motor, a manual lever to pperate said valve to openpositions, automatic means for moving said valve to closed position whenreleased, a pump, an engine to continually drive said pump, andhydraulic pressure responsive mechanism to enable said pump to be drivenby 'said engine with substantially no load on said 6 pump when saidvalve is closed and said hydraulic motor is locked in inactive podtion.

8. In a road working machine, the combination witha vehicle, ofadjustable mechanism carried thereby, a plurality o! double actinghydraulic motors connected to said mechanism to adjust the same,*aplurality -of valves one for each of said motors, a pump, an engine forcontinuously driving said pump, piping connections between the pump andthe valvesl and between the latter and said motors. said pipingconnections being constantly fully lled with liquid, and hydraulicpressure responsive mechanism to enable said pump to be drivenwith-substantially no load thereon when said valves are closed butcausing said pump to operate any one ot said motors immediately afterits valve is "opened,

9. In a road working machine, the combination with a vehicle, ofadjustable mechanism carried thereby, a double acting hydraulic motorconnected to said mechanism to adjust the same in opposite directions, avalve for controlling said motor, a pump, means to continuously drivesaid pump, hydraulic pressure responsive mechanism for controlling saidpump to rotate with closed and to produce hydraulic pressure to operatesaid motor in either direction when said valve is open in either of twopositions, and piping connections between the pump and the valve andbetween the valve and the motor kept constantly illled with liquid tosecure quick response of said motor to the opening of said valve.

.. substantially no load thereon when said valve isV 10. In a roadworking machine, the combination with a vehicle, of adjustable mechanismthereon, a hydraulic motor connected to said mechanism to adjust thesame. a valve at the operators station and connected to said motor tocontrol the same. a lever at the operators station to enable theoperator to fully open the valve accurately at any time, automaticmeansfor completely closing the valve accurately when said lever is released,a pump, means ior continuously driving said pump, hydraulic pressureresponsive mechanism for controlling said pump to operate withsubstantially no load thereon when said valveis closed, and pipingconnections maintained completely illled with liquid at all times to'secure quick response of said motor and said pump to the operation ofsaid valve.

11-. In a road working machine, the combination with a vehicle, ofadjustable mechanism carried thereby, a duid-pressure motor foradjusting said mechanism, said motor comprising a cylinder and a piston,a valve for controlling said motor, a pump, means for continuouslydriving saidA pump, and duid-pressure responsive mechanism acting onsaidpump automatically to set the. same for continued operation atsubstantially no load while maximum pressure in said cylinder ismaintained after the piston eachesthe limit o! its stroke. I

i2. In a road grading machine, the combina- I tion with a wheelsupported frame. of a road lpressure responsive mechanism forautomatically 1 relieving the load on said pump when said road ,workingvimplement meets an obstruction in its adjusting movement.

13. In a road grader, the combination with a vehicle. of a mold boardadjustably mounted thereon, means comprising a plurality of doubleacting hydraulic motors for adjusting the height 'of the lateralposition otsaid mold board relative to said vehicle, valve mechanism forcontrolling said motors, a hydraulic pump, means for driving said pumpcontinuously, and hydraulic pressure responsive mechanism for limitingthe hydraulic pressure on any of said motors when said moldI board meetsan obstruction or when such motor reaches the limit of its stroke andfor enabling said pump to be driven at substantially no load when saidvalve mechanism is closed and said motors are locked. to hold the moldboardin adjusted position.

14. In a road grader, the combination with a vehicle, of a mold boardadjustably mounted thereon, a plurality'of motors connected to said moldboard to adjust the latter and lock the same in adjusted position,"valve mechanism for controlling said motors, a hydraulic pump, means tocontinuously operate said pump, and automatic hydraulic pressureresponsive mechanism acting on saidpump to limit the pressure on anymotor when it reaches the limit of its stroke but holding the motoratits limit until said valve mechanism is closed whereupon such motorwill be locked at such limit.

'15. In a road grader, the combination with a vehicle, of meanscomprising a hydraulic motor for steering said vehicle, a road workingimplement, means comprising hydraulic motor mechanism for adjusting saidroad working implement relative to said vehicle, valve mechanism forcontrolling said hydraulic motor and said hydraulic motor mechanism, apump.' means for continuously driving said pump, and automatic hydraulicin said hydraulic motor mechanism and to enable v Isaid pump to bedriven with substantially no load thereon when said valve mechanism isclosed.

16. In a road grader, the combination with a vehicle, oi a mold boardadjustably mounted thereon, two hydraulic motors each comprising acylinder and a piston connected to said mold board to adjust theelevation and inclination Y' thereofv relative to said vehicle, aplurality of waives one foreach of said motors and connected 'to thelatter to lock the same in stationary position when said valves areclosed, a hydraulic pump, means for continuously driving said pump, and`automatic hydraulic pressure responsive mechanism acting'v directly onsaid pump to limit the hydraulic pressure in said motor when said moldboard meets an obstruction in its adjusting movement and to materiallyreduce the load on. 'the pump when said valves are closed to lock themold board in adjusted position.

1'1. In a road grader, the combination with a` vehicle comprising asupporting frame and a pair of front wheels and a pair of rear wheels,-of means comprising hydraulic motors for adjusting the leaning of thei'ront wheels and for adjusting the leaning ot the rear wheels, meanscomprising 'a hydraulic motor for shifting the rear end of said framelaterally relatively to said rear wheels, a 'mold board. meanscomprising a hydraulic motor for shitting the mold board laterally,means l comprising a pair lof hydraulic motors for ada lwdrauiic pump,and hydraulic pressure responare in their closed positions.

18. In road working apparatus, the combination with a portable frame, ofa plurality of adjustable devices carried thereby, a plurality ofhydraulic motors respectively connected to the said adjustable devices,a plurality of valves one for each oi the hydraulic motors, a rotarypump, means for continuously operating the pump, and means operableresponsively to hydraulic pressure set up by closing the said valves foracting directly on the pump to set it always to rotate at substantiallyno load when the motors are not operating.

19. In road working apparatus, the combination with a portable frame, ofa plurality of adjustable devices carried thereby, a plurality ofhydraulic motors respectively connected to the said adjustable devices,a plurality of valves one for each of the hydraulic motors, a rotarypump, a plunger operable responsively to hydraulic pressure set up byclosing the said valves for acting on the pump to set it to rotate atsubstantially no load when the motors are not operating, the plungerbeing released upon relief of the hydraulic pressure upon opening of anyone of the valves to enable the pump to move to operative position, andresilient means acting in opposition to the plunger to automatically setthe pump in operative position upon release of the plunger to therebypump fluid under pressure to the motors when any of the valves are open.

20. In road working apparatus, the combination with a. portable frame,of a plurality of adjustable devices carried thereby, a plurality ofkhydraulic motors respectively connected to the on the pump to set it torotate at substantially no load when the motors are not operating, the

plunger being released upon relief of the hydraulic pressure uponopening of any one of the valves to enable the pump to move to operativeposition, and a spring acting on the pump in opposition to the plungerto automatically set the pump in operative position upon release of theplunger, to thereby pump fluid under pressure to the motors when any ofthe valves are open.

21. A road working machine comprising, the combination with a wheeledsupporting frame including a steering wheel, of means for operating saidsteering wheel to a desired steering position and maintaining it in saidposition, said means comprising a hydraulic system including acontinuously operating pump, and hydraulic pressure responsive meansacting on said pump to operate the latter at substantially no load whenno useful work is being performed thereby.

22. A road working machine comprising, the combination with a wheeledsupporting frame including a steering wheel, of means for operating saidsteering wheel to a desired steering position and maintaining it in saidposition, said means comprising a hydraulic motor system including meansfor trapping hydraulic uid in both the intake and outlet of the motorthereof, a continuously operating pump, and means for adjusting anelement of said pump fluid output of said pump to substantially zerowhen said motor is in a fixed position.

thereby reducing 'the 23. A road working machine comprising, thecombination with a wheeled supporting frame, of a hydraulic motor systemfor adjusting a wheel to a desired position and maintaining it in saidposition, said system comprising means for trapping hydraulic uid inboth the intake and outlet of the hydraulic motor, a constantly runningpump, and means for adjusting an element of said pumpthereby reducingthe fluid output of said pump to substantially zero when said motor isin a xed position.

24. A road working machine comprising, the combination with a wheeledsupporting frame, of means for adjusting said wheel to a desiredposition and maintaining it in said position, said means comprising ahydraulic motor system including a pump and a hydraulic motor,l meansfor continuously driving said pump, adjusting an element of said pump toreduce the fluid output of said pump'to substantially zero when saidmotor is in a xed position.

25. A road working machine comprising, the combination with a supportingframe including a pair of rear supporting wheels adapted for lateraladjustment, of means for adjusting said wheels to a desired lateralposition and maintaining them in said position, said means comprising kahydraulic motor system including a pump and put oi' said pump tosubstantially zero when said motor is in a fixed position.

26. A road working machine comprising, the combination with a wheeledsupporting frame including a pair of rear supporting wheels adapted forlateral adjustment. of .a hydraulic motor system for adjusting saidwheels laterally to a desired postionand maintaining them in saidposition, said system comprising means for trapping hydraulic uid inboth the intake and outlet of the hydraulic motor, a constantly runningpump, and means for reducing the fluid output of said pump tosubstantially zero when said motor is in a xed position.

27. A road working machine comprising, the combination with a supportingframe including a pair of supporting wheels -adapted for tiltingadjustment, of means for adjusting said wheels to a desired' tiltedposition and maintaining them in said position, said means comprising .ahydraulic motor system including a pump and a hydraulic motor, means forcontinuously driving said pump, and means to'reduce the iiuid output ofsaid pump to substantially zero when said motor is in a ixed position.

28. A road working machine comprising, the combination with a wheeled4supporting frame including a pair of supporting .wheels adapted fortilting adjustment, of a hydraulic m'otor system for adjusting saidwheels toa desired tilted position and maintaining them insaid position,said system comprising means for trapping hydraulic fluid in both theintake and outlet of the hydraulic motor, a constantly running pump, andmeans for reducing the iluid output of said pump to substantially zerowhen said motor is in a xed position. v

29. A road working machine comprising, the combination with a supportingframe including a pair of rear supporting wheels adapted for adjustment,of means for adjusting said wheels to a desired position and maintainingthem in said position, said means comprising a hydraulic motor systemincluding a pump and a hydraulic and means for p motor, means forcontinuously driving said pump, 75

and means to reduce the iiuid'output of said pump to substantially zerowhen said motor is in a ilxed position.

30. A road working machine comprising, the combination with a wheeledsupporting frame including a pairof rear supporting wheels adapted foradjustment, of a hydraulic motor system for adjusting said wheels to adesired position and maintaining them in said position. said systemcomprising means for trapping hydraulic uid in both the intake andoutlet of the hydraulic motor, a constantly running pump, and means forreducing the iluid output of said pump to substantially zero when saidmotor is in a nxed position.

3 1. A road working machine comprising the combination with a supportingframe including a pair of rear supporting wheels adapted for lati eraladjustment, of means for adjusting said wheels to a desired lateralposition and maintain-y ing them in said position, said means comprisinga hydraulic motor system including a continuously operating pump, ahydraulic motor. and a control valve therefor; and means responsive to'hydraulic pressure to enable said pump to operate at substantially noload when/said motor is inactive. v 32,. A road working machinecomprising the. vcombination with a supporting frame including a pairoi' rear supporting wheels adapted for tilting adjustment, of means foradjusting .said wheels to a desired tilted position and maintaining themin said position, said means comprising a hydraulic motor systemincluding a continuousiy operating pump, a hydraulic motor and a controlvalve therefor; vand means responsive to hydraulic pressure to enablesaid pump to operate at substantially no load when said motor isinactive.

33. A road working machine comprising the combination with a supportingframe, oi'v means requiring adjustment during the operation of saidmachine to perform a road working operation, a hydraulic motor foroperating said means and holding it nxed in adjusted position, a pumpconnected to said motor, means for effecting the op- A eration of saidpump on said motor including a high pressure conduit completely filledwith liquid connecting them together, and means responsive to hydraulicpressure to cause said pump always 15' to operate at substantially noload whenever said motor is not in the act of effecting the aforesaidadjustment.

34. A road working machine comprising the combination with a supportingframe, o i' means requiring adjustment during the operation of saidmachine to perform a road working operation, a hydraulic motor connectedto a supply pipe forV operating said means, a pump connected to saidsupply pipe, said supply pipe being completely iilled with liquidbetween said motor and said` pump, means for controlling the operationof said motor by effecting control of the flow. into said supply pipefrom said pump, and means responsive to hydraulic pressure in saidsupply pipeto cause said pump always to operate at substantially no loadwhenever said motor is not inthe act of eiecting the aforesaidadjustment.

' FLOYD O. DE MILLAR.

